This invention relates generally to the pump art, and more specifically to certain new and useful improvements in diaphragm pumps of the type disclosed in U.S. Pat. Nos. 3,775,030, 3,884,598 and 3,953,154.
Diaphragm pumps of the type disclosed in these patents have a series of piston assemblies which are reciprocated by a rotating cam, the cam being canted to translate its rotation into reciprocation of the pistons. A diaphragm assembly is associated with each piston assembly, and includes a diaphragm separating a pumping chamber from a transfer chamber, the latter being between the diaphragm and piston and containing hydraulic fluid for transmitting pumping force through the diaphragm to the pumping chamber. The diaphragm is mounted on a plunger having a stem extending into a bore within the piston, the diaphragm being secured to the plunger stem by a screw.